Safety release for riveting machines



April 14, 1936. NoRlN 2,Q37,477

- SAFETY RELEASE FOR RIV TING MACHINES Filed Jan. 14, 1935 5 Sheets$heet 1 gmzle/w m April 14, 1936. A. A. NORIN 2937,47

. SAFETY RELEASE FOR RIVETING MACHINES 7 Filed Jan. 14, 1955 3 Sheets-Sheet 2 I 65 6/ 63 as 4 2 03 v EH 77a?! April 14, 1936. v A, NORlN 2,937,477

- SAFETY RELEASE FOR RIVETING MACHINES Filed Jan. 14, 1955 s Sheets-Sheet s egg Patented Apr. 14, 1936 UNITED STATES PATENT OFFICE SAFETY RELEASE FOR RIVETING MACHINES Application January 14, 1935, Serial No. 1,758

3 Claims.

This invention appertains to power presses, punches, riveting machines, and the like, of the type embodying a reciprocating head, or ram,

movable toward and away from a platen, or die. v

One of the primary objects of my invention is to provide novel means for operating the reciprocating head, or ram, from a power-driven crank shaft, or eccentric, with means for automatically releasing the ram, or head, at a predetermined tonnage at any part of the ram stroke, so that when a predetermined pressure is reached between the ram and'platen, or die, the ram will give, or release, to effectively prevent the overloading of the machine and thus prevent breakage of parts thereof and the work being operated upon. Another salient object of my invention is to provide a riveting, or like, machine having novel means for adjusting the tonnage from no load up to capacity for which the machine is designed, the device being so constructed that the use of release springs is entirely eliminated, where all backslap is overcome.

A further important object of my invention is to provide a power-driven riveting machine with a system of compound levers for transmitting power from the fiy-wheel to the ram, or head, in such a manner that the stroke of the ram through part of the total length of its movement operates with a uniform speed, the speed depending upon the links and levers between the drive shaft and ram, with novel means for releasing the ram at any predetermined tonnage;

A further object of my invention is the provision of a novelly constructed and arranged bydraulic release for the movable rams, or heads, of riveting machines with automatically operated by-pass valves releasable when a predetermined pressure is reached between the ram and die, means being provided for manually adjusting the tension of the spring of the by-pass valve so that the same will release at any desired pressure, or tonnage.

A further object of my invention is the provision of novel means for constructing the hydraulic release, whereby the same can be compactly arranged on the machine, and whereby the same can be readily taken down to permit repairs to be made thereto, such as the renewal or re-grinding of the valve seats.

A still further object of my invention is to provide a novel release for power-driven riveting machines, and the like, whichwill be durableand 'efficient in use, one that will be simple and easy to manufacture, and one which can be placed upon the market at a reasonable cost.

With these and other objects in view, the invention consists in the novel construction, arrangement, and formation of parts, as will be hereinafter morespecifically described, claimed, and illustrated in the accompanying drawings, in which drawings:-

Figure 1 is a side elevation of my improved riveting machine, showing my novel hydraulic release incorporated therewith.

Figure 2 is an enlarged, detail, vertical section taken on the line 2-2 of Figure 1, looking in the direction of the arrows, illustrating the novel system of linkage between the power-driven shaft and the ram, or riveting head.

Figure 3 is a vertical, longitudinal section through the hydraulic release taken on the line 3-3 of Figure 7, looking in the direction of the arrows. I

Figure 4 is a detail, longitudinal section through the hydraulic release taken on the line 4--4 of Figure 4, looking in the direction of the arrows and illustrating the automatically operated release, or by-pass valve.

Figure 5 is a detail, longitudinal section through the hydraulic release taken on the line 5-5 of Figure '7, looking in the direction of the arrows, illustrating the return check valve for the liquid.

Figure 6 is a detail, vertical section taken on the line 66 of Figure 3, looking in the direction of the arrows, illustrating the cylinder head of the automatic release.

Figure '7 is a view similar to Figure 6 taken on the line 1-1 of Figure 3, looking in the direction of the arrows, showing my novel removable valve plate in front elevation. I

Figure 8 is a detail section taken on the line 88 of Figure 1, looking in the direction of the arrows, illustrating the novel type of clutch and brake mechanism utilized in the machine.

Figure 9 is a vertical section taken on the line 99 of Figure 1, looking in the direction of the arrows, illustrating the mechanism employed for actuating the clutch.

Figure 10 is a detail, vertical section taken on the line Ill-40 of Figure 1, looking in the direction of the arrows, illustrating the brake, or-drag, for the operating shaft.

Figure 11 is a detail section taken on the line ll--|I of Figure 8, looking in the direction of the arrows, illustrating the clutch section carried by the fly-wheel.

Figure 12 is an enlarged detail section taken on the line |2-l2 of Figure 11, looking in the The machine A comprises a base l5 whichmay be rigidly secured to a floor, or other supporting structure, and this base rigidly supports the upstanding column 6 having the forwardly extending head, or arm Below the arm, or head, H, the column rigidly supports a platen, or like element, 8, which may constitute the support for the work being operated upon. This platen may carry a suitable die, or rivet set, l9, as shown in the present drawings.

Mounted upon the column l6 and the head I! are suitable longitudinally alined bearings 20 for rotatably supporting the main drive shaft 2|. Obviously, any desired type of anti-friction means, such as ball or roller bearings, can be utilized for supporting the shaft.

Freely rotatable on one end of the shaft 2| is a fly-Wheel 22 which can be power-driven in any desired manner and from any preferred type of prime mover, such as an electric motor. The flywheel can be operatively connected and disconnected from the main shaft 2| by a clutch 23, which will be later described in detail.

Rigidly keyed, or otherwise secured, to the drive shaft 2| is an eccentric 24 which is disposed between a pair of the bearing brackets 26. The eccentric 24 actuates a triangular-shaped head 25, which may include a hub, or collar, 26 forming a strap for rotatably receiving the eccentric.

Formed on the collar, hub, or strap, 26 is a forwardly and downwarly projecting arm 21, and a similar longer arm 28 is formed on the rear lower part of the collar, hub, or strap.

Reciprocally mounted within the head, or arm, I! in any preferred manner is the ram, or operating plunger, 29, and this plunger is movable toward and away from the platen 8 and the rivet set, or die, carried thereby.

A link 39 is pivotally connected to the arm 21 and to the upper end of the plunger, or ram, 29.

Rockably mounted on the frame of the machine below and at one side of the main drive shaft 2| is a supporting shaft 3|. The supporting shaft 3| is operatively connected to the arm 28 of the triangular-shaped operating head 25 by means of a novel toggle 32.

This toggle 32 includes an upper lever 33 pivotally connected to the outer end of the arm 28 and to the upperends of a pair of levers, or cranks, 34. These cranks 34 receive the lever 33 therebetween, and a suitable pivot pin 35 connects these members together.

The cranks, or levers, 34 can be rigidly formed on, or rigidly secured to, the supporting rock shaft 3|, and for ease in assembling the cranks are formedon a hub, or sleeve, 36, which can be keyed to the center rock shaft 3|.

The-rock shaft 3| extends laterally of the ram, or plunger, 29 and is operatively connected to the novel hydraulic release 31, which will now be described. 3

My novel hydraulic release 3'! embodies 9. cylinder body 38 having formed therein a cylinder chamber 39, in which is reciprocally mounted the piston 40.

Formed in the cylinder body 38 is an enlarged liquid-receiving chamber 4|, which communicates with the cylinder chamber 39, and longitudinally extending by-pass passageways42 and 43 and a return passageway 44.

Secured to the piston 40 is a piston rod 45 which extends exteriorly of the cylinder body through a suitable packing gland 46.

The cylinder body 38 has removably connected thereto, by the use of suitable cap bolts, or the like, 41, a cylinder head 48. This cylinder head 48 has formed therein a central cavity 49, which is adapted to communicate and aline with the cylinder chamber 40 and radially extending branch cavities 59, 5|, and 52. These cavities 59, 5|, and 52 are adapted to communicate and aline with the passageways 42, 43, and 44, respectively.

Removably positioned between the cylinder body 38 and the cylinder head 48 is a packing and valve plate 53. This packing and valve plate 53 is provided with a central opening 54 which registers with the cylinder chamber 39 and the central cavity 49 of the cylinder head.

Formed in the packing and valve plate are ports 55, 56 and 51, which form valve seats, and these ports allow communication to be had between the passageways 42, 43, and 44 and the branch cavities 50, 5|, and 52.

A suitable non-compressible liquid, such as oil, is introduced into the chambers 39 and 4| and the various passageways and cavities through the filling and clean-out plugs 58 carried by the cylinder body and head.

Obviously, when the piston is moved forwardly, the liquid in the cylinder chamber will be placed under pressure and the same will be forced toward the cylinder head with its cavities and into the various passageways. The flow of the liquid through these passageways is controlled in a novel manner.

Normally seated on the valve seat of the port is the automatic release valve 59, the stem 60 of which is slidably mounted in an adjusting sleeve 6|, threaded into the cylinder body 38. A packing gland 62 is placed about the adjustable sleeve so that the leakage of the liquid past the sleeve will be prevented.

An expansion spring 63 is coiled about the stem of the valve, and the opposite ends thereof bear respectively against the valve 59 and the adjustable sleeve. becomes great enough to overcome the tension of the spring 63, the valve will unseat and the liquid will flow through the passageway 42. By adjusting the sleeve 6|, the tension of the spring 63 can be regulated so that the valve will unseat at the preferred pressure.

This valve is adapted to be set and adjusted at the plant to suit the individual character of the work being operated upon.

In order to prevent any possible error on the part of the operators, the release is also provided with means to permit the by-passing of the fluid when the greatest tonnage is reached for which the machine is designed.

This release comprises a valve 65 for the port 56, and the valve is provided with a valve stem 66 slidably mounted in an adjustable sleeve 67 threaded into the cylinder body. As stated, the

' sleeve 61 is adjusted so that the expansion spring 68 will be set for the capacity of the machine,

Obviously, when the pressure '7 after which the opening. for the sleeve 61 is,sealed by aeclosure .plug v69..

From the description so far, 1t can be seen. that the hydraulic releases operates as follows:-

Upon forward movementof the piston 48 ,(to.

the right, referring to Figure 3 of the drawings), the liquidwill be forced out of the cylinder head and will actuate the valves 59 and 65. When pressure reaches the predetermined tonnage, as defined by the spring 63, the valve willunseat and the liquid will flow into the chamber 4| in rear of the piston.

If for any reason the tension of the spring 63 has been adjusted beyond the capacity of the machine, the valve 65 will be unseated when capacity pressure is reached, and thus the liquid will by-pass through the passageway 43. Upon rearward movement of the piston, the liquid will be forced into the passageway 4| and free communication is had around the piston by means of the check valve 10.

My novel hydraulic release is connected with the rock shaft 3| in the following manner:-

The outer end of the piston rod 45 carries a cross-head H to which is pivotally connected the forwardly extending connecting rods 12, which are in turn connected by means of a cross-pin 13 with a pair of cranks 14. These cranks 14 can be formed on a sleeve, or hub, 15, which is keyed, or otherwise secured, to the rock shaft 3|. Thus, there is a direct connection between the piston and the toggle 32.

In operation of my improved device, when the work has been placed between the platen l8 and the ram, or plunger, 29, and the fiy-wheel 22 is operatively connected to the drive shaft 2| through the clutch 23, the eccentric 24 will be set in operation and the operating head 25 will be alternately raised and lowered in a substantially circular path.

Normally, the toggle is held against movement at the pivot pin 35 through the automatic hydraulic release, and thus the head 25 swings on the link 33 and the pin of the arm 28 as a pivot.

During normal operation, the plunger, or ram, 29 is alternately raised and lowered. However, should the pressure exceed or reach the predetermined set tonnage, the valve 59 will be forced off its seat and inward movement of the piston 40 is permitted' Thus, the toggle will break and in effect the head 25 will rock on the link 38 as a pivot, and further downward movement of the plunger, or ram, 29 will pe prevented.

The breaking of the toggle does not hinder the rotation of the eccentric in any way, and consequently upon the raising of the operating head 25, the parts will be returned to normal and the machine is ready for its next operation.

Referring to the clutch 23, it will be noted that the hub of the fiy-wheel 22 carries a clutch section 80. This clutch section 88 includes spaced recesses 8| arranged in an annular path in which are fitted hardened steel pins 82 which form the clutch face. The pins of the pairs of pins 82 are provided respectively with abutment faces 83 and inclined release faces 84.

Facing the clutch section 88 is a clutch section 85 which is keyed to the drive shaft 2|. Slidably mounted within the clutch section 85 is a spring-pressed clutch pin 88, which is normally urged toward the clutch face of the section 80,

andrthis. clutch pin normally functionsto. con-.;

nect the clutch sections 80 and 85 together.

Formed on the clutch pin.86 is alaterally extending, cam-shapedfinger 81, andthe. clutchpin 86 can be. moved away from the clutch-section 80 by means .ofa wedgeshaped operating, arm 88. acting against the cam-shaped finger; 81; The :arm 88 is rigidly connected to abell crank; or similar, lever, 89, which is rockably; mountedatits angle on theframe of the machine.

Aspring-Sll is utilized for normallyurging: the wedge-shaped arm 88 in the path of the finger 81, so as to normally hold the clutch pin 86 away from the clutch section 80.

The bell crank and the arm 88 are adapted to be operated from a foot treadle 9|, which is operatively connected through the medium of a crank 92 and connecting rod 93 to the bell crank 89. Thus, when pressure is applied to the foot treadle, the bell crank will be rocked and the arm will be moved away from the cam-shaped finger 81, and the clutch will automatically engage. When it is desired to stop the operation of the machine, pressure is released from the treadle.

To bring about the instant stopping of the drive shaft upon the release of the treadle, a brake, or drag, 94 is provided. This brake, or drag, 94 includes a brake drum 95 rigidly fastened to the clutch section 85. The drum is adapted to be engaged by semi-circular brake shoes 96, which can be adjusted relative to one another and relative to the drum by means of screws 91. The shoes are anchored by means of a pin 98 to the frame of the machine.

Y Changes in details may be made without departing from the spirit or the scope of this invention, but what I claim as new is:-

1. In a power-operated machine, a frame, a drive shaft rotatably supported by the frame, means for rotating the shaft, an eccentric on the shaft, a head operated by the eccentric, a pair of angularly disposed arms on the head, a plunger slidably mounted on the frame a link connection between one arm and the plunger, a rock shaft, a toggle between the other arm and the rock shaft including a pair of levers pivotally connected together, one of said levers being pivotally connected to the last mentioned arm and the other of said levers being secured to the rock shaft, a crank arm on the rock shaft, a cylinder, a piston slidable in the cylinder, a piston rod connected with the piston extending exteriorly of the cylinder, a cross-head secured to the piston rod, links connecting the cross-head with the crank arm, by-pass and return passageways around the cylinder, a check valve for the return pasageway, and

spring-pressed adjustable valves for the by-pass passageways.

2. In a hydraulic release for power-operated machines, a cylinder body having a cylinder chamber and a storage chamber therein connected with one another at one end, a cylinder head having a central and branch cavities connected with the cylinder body, a packing and valve plate disposed between the cylinder head and cylinder body, having a central opening and ports around said opening communicating with the branch cavities, the cylinder body having by-pass and return passageways communicating with the storage chamber and the ports in the plate, a piston movable in the cylinder chamber, a pair of adjustable spring-pressed valves seated on the walls of certain of said ports, an oppositely directed, springpressed check valve seated on the wall of the other port.

3. In a power-operated machine, a frame, a drive shaft rotably supported by the frame, means for rotating the shaft, an eccentric on the shaft, a head operated by the eccentric, a pair of angularly disposed arms on the head, a plunger slidably mounted on the frame, a link connection between one arm and the plunger, a rock shaft, a toggle between the other arm and the rock shaft including a pair of levers pivotally connected together, one of said levers being pivotally connected to the last-mentioned arm, and the other of said levers being secured to the rock shaft, a crank arm on the rock shaft, a stationary cylinder, a piston slidably mounted in the cylinder, a piston rod connected with the piston extending exteriorly of the cylinder, a. cross head secured to the piston rod, and links connecting the cross head with the crank arm.

ALLAN A. NORIN. 

